Thanks to everyone who responded on the question of carrying a spare bottle of fuel around in case of emergency empty tank. I can see the dangers of attempting something like this. Someone said it was even illegal ( can anyone confirm that). The only reasonable possibility was the MSR bottles that someone suggested. But, I had a brainstorm ... what if ... you had a little bottle or bladder (1/2 pint or so) that you could fill with fuel, seal, and then drop it into the fuel tank itself? Then if you ever run out of gas, you could open up the tank, fish out the bottle/bladder and empty it into the tank and ... presto ... you've got another 5 miles of so to find a gas station. Anyone ever heard of that idea or know of a product that works like that?
1st of all, you wouldnt be able to get it out of the fuel tank and second of all, why not fill the last ½ pint into the fuel tank instead?
Either way, you will have ½ pint fuel in the tank, the only diffrence is just if you can use it or not.
If it's illegal or not depends on your country. Here in Denmark, i can drive with 1 L fuel in an approved container, but personally, i wouldn't and i would not at all put it underneath the seat, as it gets quite hot there when you drive. Like when you've put beers down there, then driven to a party and then have 14 warm beers. Mmmmm delicious, right?
The only diffrence is that fuel evaporates even at -15 degrees celcius (been there, got it on my fingers, damn it hurts in the cold), so it will only evapourate more when heated up, and this is when it becomes bad, as this is flammable gas.